The fifth season of Jersey Shore started off with a bang Thursday, as the lingering tension between Snooki and The Situation — over a hook-up he swears to and she denies — explodes in a confrontation between the pint-sized starlet and his brash new sidekick, “The Unit.”

The episode unfolds as the cast returns from Florence, Italy, only to — What else?!? — celebrate their homecoming at a Seaside Heights bar. Everyone is there: friends and family, including Snooki’s serious boyfriend Jionni LaValle, who’s still clueless to the whispers that his gal pal hooked up with The Sitch. (He actually buys him drinks all night.)

A brazen bodybuilder, The Unit’s comparable to The Situation, minus the good manners: When Jionni takes a bathroom break, he immediately lays into Snooki about how he witnessed she and The Situation hooking up — and won’t hesitate to tell him.